Author Topic: Uni-T UT181A - Board revisions, ESD robustness?  (Read 3522 times)

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Offline Fungus

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Re: Uni-T UT181A - Board revisions, ESD robustness?
« Reply #25 on: December 17, 2019, 01:26:38 pm »
It's our buddy who made debunk video ...

I remember it well, I just didn't remember the name.
 

Offline DarrenWalker

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Re: Uni-T UT181A - Board revisions, ESD robustness?
« Reply #26 on: December 17, 2019, 10:57:17 pm »
Unfortunately BT is NOT reliable on the UNI-T UT181A
It's too bad really as it's a huge part of the appeal on this meter.
 

Offline DarrenWalker

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Re: Uni-T UT181A - Board revisions, ESD robustness?
« Reply #27 on: December 17, 2019, 11:13:24 pm »
Joe,
My crew have used those same meters for over 5 years and we haven't had one issue.  :wtf:
Why keep trying to blow smoke when there's isn't any?
Hmmm, I can think of another use for that grill starter. :box:

« Last Edit: December 18, 2019, 05:46:32 pm by DarrenWalker »
 

Offline DarrenWalker

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Re: Uni-T UT181A - Board revisions, ESD robustness?
« Reply #28 on: December 17, 2019, 11:19:27 pm »
>>>Welcome to the EEVBLOG site

Thankyou, Dave is a trooper. 100% respect to him and this great EEVBLOG Forum.
 

Offline DarrenWalker

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Re: Uni-T UT181A - Board revisions, ESD robustness?
« Reply #29 on: December 18, 2019, 05:55:06 pm »
I spoke with a UNI-T engineer last year, they don't have any plans on making the Firmware user upgradeable (at least in the short term), which is really too bad. That could have easily resolved a-lot of the dmm's snafus.

Darren
 

Offline mcinque

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Re: Uni-T UT181A - Board revisions, ESD robustness?
« Reply #30 on: December 19, 2019, 09:41:53 pm »
There is a huge difference in components when you purchase any UNI-T from eBay or from a "known" name like Farnell or Distrelec.

It seems UNI-T have different markets and only purchasing from reliable distributors you can get the "certified" version (CE in my case).

My UT61s from Distrelec have decent input protection with much more MOVs in respect to the ones I saw on YouTube reviews or in teardown images on the web.

I'm not saying that UNI-T can challenge Fluke, but those tests aren't decisive; the DUT may come from a chinese eBay reseller in the "cheaper version" with almost no input protection.
 
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Offline DarrenWalker

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Re: Uni-T UT181A - Board revisions, ESD robustness?
« Reply #31 on: December 20, 2019, 01:20:26 am »
That's a good point :-+. I realise European standards are usually enforced allowing for a better overall product. However,  in all of my reviews the UNI-T multimeters are sourced from regular Ebay/Ali *  vendors including the UT181A which was surprisingly well put together. It's very easy to cherry pick a multimeter for a review but its alot more useful to the public in general if the meter is sourced from a regular vendor to gauge the Q/A correctly.
 

Offline spiff72

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Re: Uni-T UT181A - Board revisions, ESD robustness?
« Reply #32 on: June 18, 2020, 01:26:35 pm »
If you have a direct line to an engineer at UNI-T, why wouldn't you inquire about possible board revisions to this to address the ESD concerns about it?  Send them a link to Joe's video perhaps?
 

Offline spiff72

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Re: Uni-T UT181A - Board revisions, ESD robustness?
« Reply #33 on: June 24, 2020, 11:12:47 pm »
I know this is an older thread, but I just wanted to chime in and say that I just ordered and received a Triplett 9065, which appears to be exactly the same as this Uni-T UT181A.  Just for grins I opened up the back to see the PCB, and it is marked as 20130530-6  UT181A-MAIN on the top of the board.  In comparing to the video from joeqsmith, there appears to be a few changes in the lower right (when viewing the back of the board (battery connector side).  I see a line of three small vias that were reoriented to be vertical instead of horizontal, and there may be a half-round clearance added around these on the ground plane.  I also see the L-slot that was added at the bottom of the smaller fuse, and one thing that I am not sure is a trick of the camera, but there is a trace from the small SMT cap (C112) to the right of the larger fuse that is visible in Joe's video, but is not visible on my board.  It may be on the other side of the board, but it is MUCH more visible in Joe's video, so I wonder if that trace was shifted to the other side of the PCB??

Anyway, do any of these changes appear to reflect possible changes to resolve the ESD issues that Joe fixed in his meter?  Just curious...  Photos of my board are attached.

If anyone wonders, I ordered this meter from Amazon ($250) but it is also available from TEquipment.net as well.  It is a bit cheaper at TEquipment ($223), but I opted for the Amazon purchase for easier returns if it turned out to be different that the Uni-T model (and it was still in transit to TE when I chatted with them prior to ordering).
 

Offline spiff72

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Re: Uni-T UT181A - Board revisions, ESD robustness?
« Reply #34 on: June 24, 2020, 11:13:50 pm »
One more image of my board, and a screen grab from joe's video:
 

Offline oktay50000

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Re: Uni-T UT181A - Board revisions, ESD robustness?
« Reply #35 on: July 23, 2020, 07:54:57 am »
 Triplett 9065
Is it exactly the same model as 181a or it has better isolation,or any changes inside???? Or just a branding game
 

Offline JACKENPACKEN

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Re: Uni-T UT181A - Board revisions, ESD robustness?
« Reply #36 on: November 07, 2020, 07:10:48 pm »
I see the difference. i ques the picture below is your triplett. seems there is cap under the top fuse and metallic cap divider. would love to see joes comparison between these two DMM's 
 

Online joeqsmith

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Re: Uni-T UT181A - Board revisions, ESD robustness?
« Reply #37 on: November 08, 2020, 03:16:30 am »
Appears they changed the case mold to add that plastic insulator that feeds through the area near the fuse.   Guessing that actually had it tested.   Hard to say if they did anything to address the the typical UNI-T ESD sensitivity that I've grown to expect from them.  Just looking at the new board, my guess is they have not. 
How electrically robust is your meter?? https://www.youtube.com/channel/UCsK99WXk9VhcghnAauTBsbg
 


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